高荧光量子效率的分子分散型聚芴衍生物的放大自发发射特性

通过将掺杂剂单元用化学键接到聚芴的侧链上,实现了掺杂剂单元在高分子主体中的分子水平分散,开发了一种新型的基于掺杂剂/主体材料体系的分子分散型蓝光聚芴衍生物.与纯聚芴相比,这种新的分子分散型蓝光聚芴衍生物具有很高的荧光量子效率.以这种新的分子分散型蓝光聚芴衍生物为增益介质的激光器件,在Nd:YAG 355 nm脉冲激光泵浦下,获得了较好的放大自发发射光谱,阈值达到0.25 m J/(pulse cm2).从光物理的角度对薄膜的光学增益和光学损耗进行了定量运算和分析,经过拟合发现,当泵浦能量为0.06m J/pulse时,该聚芴衍生物增益系数可达23.08 cm-1,损耗系数为6.96 cm-1.优良的放大自发发射特性表明该聚芴衍生物是非常好的有机激光增益介质材料.

Amplified spontaneous emission from a molecular dispersed polyfluorene derivative with high photoluminescence efficiency

Using of conjugated polymers as gain media for lasers and optical amplifiers has gained rapid progress. By covalently attaching a dopant to the side chain of a conjugated polymer host, we developed a molecular dispersed polyfluorene derivative based on dopant/host emitter system with blue emission. Compared with polyfluorene, this molecular dispersed polyfluorene derivative emits blue light and shows high photoluminescence（PL） quantum efficiency. And this molecular dispersed polyfluorene derivative, as gain media, was used in the studies of amplified spontaneous emission（ASE） and lasing action. It can be seen that the molecular dispersed polyfluorene derivative emits a narrowed emissive spectrum when optically pumping at 355 nm laser, showing better ASE action. The threshold energy was as low as 0.25 m J/（pulse cm2）, and the net gain and loss reached 23.08 and 6.96 cm-1, respectively. The results indicated that the molecular dispersed polyfluorene derivative could be a promising candidate as gain medium for the fabrication of blue polymer lasers.